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        <p>Library Version 11.2.5.3</p>
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            <h2 class="title" style="clear: both"><a id="DBOpenFlags"></a>Database Open Flags</h2>
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      <p>
		The following are the flags that you may want to use at database open time.  
		Note that this list is not exhaustive — it includes only those flags likely 
		to be of interest for introductory, single-threaded
		database applications. For a complete list of the flags available to you, see the 
		
		<em class="citetitle">Berkeley DB C++ API Reference Guide.</em>
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        <h3 class="title">Note</h3>
        <p>
		To specify more than one flag on the call to 
		
        <span><code class="methodname">Db::open()</code>,</span>
		you must bitwise inclusively OR them together:
	</p>
        <a id="c_db3"></a>
        <pre class="programlisting">u_int32_t open_flags = DB_CREATE | DB_EXCL;</pre>
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				<code class="literal">DB_CREATE</code>
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				If the database does not currently exist, create it. By default, the database open 
				fails if the database does not already exist.
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            <p>
				<code class="literal">DB_EXCL</code>
			</p>
            <p>
				Exclusive database creation. Causes the database open to fail if the database 
				already exists.  This flag is only meaningful when used with 
				<code class="literal">DB_CREATE</code>.
			</p>
          </li>
          <li>
            <p>
				<code class="literal">DB_RDONLY</code>
			</p>
            <p>
				Open the database for read operations only. Causes any subsequent database write 
				operations to fail.
			</p>
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            <p>
				<code class="literal">DB_TRUNCATE</code>
			</p>
            <p>
				Physically truncate (empty) the on-disk file that contains the database. 
				Causes DB to delete all databases physically contained in that file.
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